Microcimbali Troubleshooting - multiple pulls to start flow

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#1: Post by cidadao »

In January I acquired a 1974 Microcimbali - makes great coffee, I love the thing.

In last three months it's seen more use than in the previous 48 years combined-about 4-5 drinks a day-and I'm worried I've pushed it to the breaking point. In the last week or so, the machine has begun to require many actuations of the lever (as many as eight or nine) for the flow to begin. It's not choking; the level simply rises back up immediately. No changes to dose, bean, or grind setting in the recent weeks. The coffee still comes out okay, pretty much the same as before, but the lever is creaky and the whole operation feels very dubious. Any idea what might be going on? Thanks!

EDIT: the gaskets were all swapped out with the OE Kit by seller.


#2: Post by XS750AU »

Have you cleaned the little disk valve that is held in by the shower screen? Unscrew the 2 nuts and drop the shower screen and then clean the little rubber disk. You would think that the boiler pressure would be sufficient to fill the cylinder, but I have noticed that if the pre-infusion does not drip out then the disk valve needs cleaning. You should hear a hiss as the water is sucked into the cylinder due to the vacuum formed by lifting the piston.
If that does not fix it, then I would suggest the piston may need to be removed and the 2 O rings replaced.
They are a very simple machine to work on. Good luck.